1. Field of the Invention
The invention involves a prosthetic joint for use by amputees, and, more particularly, a prosthetic joint utilizing polymeric linkage which provides intrinsic extension bias, as exemplified by a prosthetic knee joint.
2. Description of the Prior Art
Various knee joints have been designed for use by above-knee amputees. Recent designs have included four-bar linkage which provides a high center of rotation and inherent stability. However, these knee joints generally have been complicated in structure, including complex spring and/or hydraulic mechanisms to achieve the desired performance, which has resulted in high cost, heavy weight, and inadequate reliability.
What is needed is a prosthetic joint which provides an intrinsic extension assist, and is lightweight, noise free, simple in structure, reliable in operation and relatively inexpensive.